№2. Решить уравнение: 1) 14 – (2 + 3x – x²) = x² + 4x -9, 2) 15 - (2x² - 4x) - (7x - 2x²) = 0.

Решим каждое уравнение: 1) $$14 - (2 + 3x - x^2) = x^2 + 4x - 9$$ $$14 - 2 - 3x + x^2 = x^2 + 4x - 9$$ $$12 - 3x + x^2 - x^2 - 4x + 9 = 0$$ $$-7x + 21 = 0$$ $$-7x = -21$$ $$x = 3$$ 2) $$15 - (2x^2 - 4x) - (7x - 2x^2) = 0$$ $$15 - 2x^2 + 4x - 7x + 2x^2 = 0$$ $$15 - 3x = 0$$ $$3x = 15$$ $$x = 5$$